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991.
An‐Hsiang Wang Chih‐Chen Tseng Shie‐Chang Jeng Kai‐I Huang 《Journal of the Society for Information Display》2008,16(1):101-106
Abstract— This study used several electronic‐book (e‐book) displays (a conventional LCD under transmissive mode, a conventional LCD under reflective mode, a Ch‐LC display, and an e‐ink display) to investigate the effect of e‐book inclination (105° and 135°) and ambient illuminance (200, 800, 1500, and 2200 lux) on the comprehension of subjects. Results indicate that the ambient illuminance does not significantly affect the comprehension of subjects. However, their comprehension differed significantly when using different e‐book displays. In addition, the interaction between illuminance and e‐book display had a significant effect on their comprehension. When the ambient illuminance was set at 800, 1500, and 2200 lux, the subjects' comprehension for reading different e‐book displays did not show a significant difference. When the ambient illuminance was set at 200 lux, however, their comprehension for reading a Ch‐LC display, an e‐ink display, and a conventional LCD under transmissive mode were better than their comprehension of reading a conventional LCD under reflective mode. Regarding the inclination for using e‐books, the subjects' comprehension was better under 105° than that under 135°. 相似文献
992.
993.
This paper presents an online measurement-based admission control scheme on the basis that the aggregate VBR video traffic is lognormally distributed. The proposed scheme consists of two components: measurement process and admission decision. The measurement process applies a linear Kalman filter to estimate statistical parameters of aggregate VBR video traffic. The estimated statistical parameters are used to calculate the effective bandwidth for admission decision. Variable bit rate (VBR) video traffic with high data rate is expected to occupy a dominant proportion of bandwidth for future wireless broadband home networks. To guarantee quality-of-service (QoS) of such VBR video streams, while achieving a high level of channel utilization, an efficient admission control scheme is urgently required, especially for emerging wireless multimedia indoor services, such as HDTV, online video game, etc. The proposed scheme is computationally efficient and accurate without much prior traffic information. Simulation results verify its effectiveness and show that it performs well for both a small number of connections and a large number of connections. 相似文献
994.
This study introduces a fuzzy control design method for nonlinear systems with a guaranteed H∞ model reference tracking performance. First, the Takagi and Sugeno (TS) fuzzy model is employed to represent a nonlinear system. Next, based on the fuzzy model, a fuzzy observer-based fuzzy controller is developed to reduce the tracking error as small as possible for all bounded reference inputs. The advantage of proposed tracking control design is that only a simple fuzzy controller is used in our approach without feedback linearization technique and complicated adaptive scheme. By the proposed method, the fuzzy tracking control design problem is parameterized in terms of a linear matrix inequality problem (LMIP). The LMIP can be solved very efficiently using the convex optimization techniques. Simulation example is given to illustrate the design procedures and tracking performance of the proposed method 相似文献
995.
In the hot gas desulfurization process using iron oxide sorbent, the regeneration of the sulfided iron oxide sorbent consists of two reactions: the oxidation of iron sulfide with air, and its reaction with the sulfur dioxide formed during the air oxidation. This part describes the kinetic studies on the reactions of iron sulfide (formed by the reactions of Fe2O3 with H2CO mixture and subsequendy with H2S) with oxygen and sulfur dioxide. The experimental and analysis procedures used are similar to those outlined in Part I of this paper.The activation energies for the oxygen and the sulfur dioxide reactions are found to be 15.63 and 17.5 kcal/mol, respectively. Notably, the product oxides formed in the two cases are different. With air, the reaction is fast and the final product is Fe2O3, whereas with SO2, the major product is Fe3O4, which slowly oxidizes to Fe2O3 in a secondary step. Also, in the latter reaction elemental sulfur is formed. 相似文献
996.
997.
雪山隧道共有3組通風堅井:2#豎井雖位於倒吊子向斜構造之北翼,但因地質情況尚佳,故施工期間並未施作地質弱带處理作業;3#豎井位置之地層屬始新世之四稜砂岩區,因岩盤不連續面發達,透水性高,滲水量大,需經灌漿處理,才能繼續施工,其中排氣井採短階水玻璃液(LiquidGlass)灌漿,進氣井採深孔皂土水泥灌漿;!#豎井因位於鶯子瀨向斜南翼所形成之單斜構造上且地質情況不良,正進行深孔皂土水泥灌漿作業。目前2#,3#豎井已開挖完成,1#豎井正進行昇井工法之導孔鑽孔作業,故擬以雪山隧道豎井地質弱带處理案為例,說明地質弱带之地質特性及處理原則,期能對爾後類似案例提供處理思維方向。 相似文献
998.
The surface band diagram of InN and band structure of the InN/GaN interface were studied using ultraviolet photoemissive yield spectroscopy and X-ray photoemission spectroscopy (XPS). The surface work function and the difference between the Fermi level and the conduction band minimum of InN were determined by ultraviolet photoemissive yield measurement. The band offsets and surface band bending were determined using XPS. Both spectra proposed downward band bending of the InN surface. Moreover, the Schottky barrier height (SBH) of the InN/GaN interface is determined (1.5 eV). Comparison of the measured SBH with our previous results by electrical measurement is discussed. The physical quantities derived in this work provide important information for use in future studies of InN and InN/GaN heterostructures. 相似文献
999.
Photo-reduction of Cr(VI) in a solution with single or multi-inorganic anions was evaluated. The results show that 38.5 microM Cr(VI) is photo-reduced in the presence of NO(3)(-) at pH 1. The photolysis of NO(3)(-), producing NO(2)(-) or H(2)O(2), may contribute to Cr(VI) reduction. The addition of 0.001-0.1 M chlorite to NO(3)(-) enhanced Cr(VI) photo-reduction when 35.8 microM Fe(III) was present. This enhancement was the combinative result of photolysis of NO(3)(-) and Fe-Cl complexes, leading to the formation of NO(2)(-) and Fe(II), respectively, for Cr(VI) reduction. On the contrary, a significant decrease in Cr(VI) photo-reduction was observed with the addition of PO(4)(3-) and SO(4)(2-). This decrease was due to their strong competition with Fe(III) from Cl(-), resulting in a marked decrease in the concentrations of Fe-Cl complexes. The results suggest that a direct irradiation of acidic wastewaters containing Cl(-), NO(3)(-), and Fe(III) is a feasible strategy for eliminating Cr(VI). 相似文献
1000.
Lin MD Rau JY Tseng HH Wey MY Chu CW Lin YH Wei MC Lee CH 《Journal of hazardous materials》2008,156(1-3):223-229
Large-scale open burning of joss paper is an important ritual practice for deity worshipping during Buddhist and Taoist festivals. Since Buddhism and Taoism are two of the most popular religions in Chinese societies and some Asian countries, the impact of joss paper burning on the air quality needs further investigation. This study explores the concentrations of polycyclic aromatic hydrocarbons (PAHs) in ambient air during one of the most important festivals, in which large-scale burning of joss paper occurs in temples and in people's houses. The PAH concentrations were measured simultaneously at a temple site and a background site during both the festival and non-festive (ordinary) periods. Each ambient sample was extracted by the Soxhlet analytical method (for both particle-bound and gas-phase) and analyzed with gas chromatography. Experimental results indicate that the total PAH concentration during the festival period is approximately 4.2 times higher than that during the ordinary period (5384 ng m(-3) vs. 1275 ng m(-3)). This study also employed statistical methods including diagnostic ratios and principal component analysis (PCA) to identify the possible PAH emission sources. Joss paper burning and vehicular emissions are identified as the principal sources of airborne PAHs during the large-scale open-burning event. The results of this work provide useful information for public awareness concerning PAH emission from the open burning of joss paper. 相似文献